Ecotech GTS Control Logic RIV-601P/S, Technical Description And Application Manual

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MASP 28-GB rev. 0 NOV10
FALSE ALARMS FROM ELECTROMAGNETIC EMISSIONS
4.0 How to reduce the electromagnetic noise
In order to obtain good results and to eliminate or minimize the
risk of false alarms, it is necessary to operate on two fronts: on
the equipment that generate noise and on systems and wiring
of spark detectors.
4.1 Stopping electromagnetic emission on source
equipment
- Ground connection, verifying it is a good ground.
Connect to ground all metallic parts of the equip-
ment, metallic conduits, metallic tubing for cables,
shields of shielded cables, so as to discharge to the
ground the electromagnetic fields present or running
by.
- Use shielded wiring, and keep it physically separate
from other wiring. If possible run it through metallic
tubing. Remember that nearby cables are influenced
by induction caused by current variations.
- Insert stop inductors on connections to common
power electrical lines so as to prevent electromag-
netic noise from running towards other equipment
and systems.
4.2 Stopping electromagnetic noise on spark detector
systems
It is necessary to prevent noise from reaching the
detector.
- Connect to ground all metallic parts of the system,
the detector enclosure, the dust extraction conduits,
metallic tubing for cables, shields for shielded cables.
Verify that ground is good. Remember that a bad
ground connection spreads the electromagnetic noise.
- Use shielded wiring, and keep it physically separate
from other wiring. If possible put it into a metallic
tubing. Remember that nearby cables are influenced
by induction caused by current variations.
Keep separate 24Vdc wiring from higher voltage
wiring (keeping in mind that 24Vdc wiring enters inside
the detector electronic circuit).
GROUND CONNECTION AND WIRING SEPARATION
Fig. 6 - Control panel connected to ground
Fig. 7 - Electric motor connected to ground
Fig. 8 - Dust extraction conduit connected to ground
Fig. 9 - Metallic tubing for cables connected to ground
Fig. 10 - Shielded wiring connected to ground
Fig. 11 - Plastic conduit with different levels to separate different
cables (electronic signals, DC low power, AC power)